Bowl structure and wearing parts for gyratory crushers



Sept. 20, 1955 J. P. BURLS 2,718,358

BOWL STRUCTURE AND WEARING PARTS FOR GYRATORY CRUSHERS F'iled July G, 1951 2 Sheets-Sheet l w" mark Jef/arneys Sept. 20, 1955 J, P. BURLS 2,718,358

BOWL STRUCTURE AND WEARING PARTS FOR GYRATORY CRUSHEIRS Filed July 6, 1951 2 Sheets-Sheet 2 j?? We?? 07 ./frfarvfqys Patented Sept. 20, 1955 United States Patent Oce BOWL STRUCTURE AND WEARING PARTS FOR GYRATORY CRUSHERS John P. Burls, Johannesburg, Transvaal, Union of South Africa, assignnr to Nordberg Manufacturing Company, Milwaukee, Wis., a corporation of Wisconsin Application July 6, 1951, Serial No. 235,402

Claims. (Cl. 241-156) This invention relates to gyratory Crushers of the kind in which the crushing jaws or members are provided respectively by a stationary bowl or the equivalent, (which will for convenience be called a bowl herein), and a gyratory head. The bowl is mounted to permit adjustment to compensate for wear or to alter the size of the discharged product. For instance, the bowl may be mounted on an adjustment ring with which it is engaged by screw-threading.

Conventionally, the bowl and head are each tted with liners which are exposed for inspection or replacement by unscrewing the bowl and removing it. As the bowl is a massive structure, this is a major operation which puts the crusher out of action for some time, and necessitates the use of equipment such as a crane or derrick to handle the bowl.

One object of the present invention is to provide a construction which facilitates replacement of worn elements.

Another object is to effect an improvement in the crushing action of the cavity defined between the opposed crushing members.

In gyratory crushers the material being crushed is comminuted by a series of rapid hammer-like blows as it passes between the mantle and the bowl liner. In general, the cavity between the crushing members decreases between intake and discharge, and near the discharge end the crushing faces may be parallel for some distance.

It has hitherto been considered necessary for the eicient operation of gyratory crushers to impart a plurality of blows to each individual particle of material being crushed. The inventor has found that, contrary to this belief, etiicient crushing is achieved if the crushing zone is so restricted in length that at least the greater part of the material is struck a single blow only. According to the present invention the crushing zone of the crusher is dimensioned for the majority at least of the particles of material passing between the crushing elements to be struck a single blow before they are discharged from the zone. Preferably the crushing faces are parallel with one another. There may be a single crushing zone, or several; but in the latter case each zone is so designed that at least most of the particles passing therethrough are struck a single blow.

According to the disclosure hereof, the crusher includes a hollow member supported at least partly above the crushing zone and a ring providing the upper crushing element and detachably secured to and surrounded by the member, the inside diameter of the hollow member being greater than the outside diameter of the ring; the hollow member being open from above to permit the ring to be lowered into position through and within it.

Further, the inside diameter of the hollow member exceeds in magnitude the outside diameter ofthe lower crushing element.

When the crushing elements are to be inspected or renewed, their securing means-which are purposely made simple and readily accessible-are detached, and

the elements are in turn lifted upwards through the supporting member. New elements are then lowered into position and secured. Little or no dismantling of the crusher structure is called for, and the operation is there fore quick and easy.

To obtain the above-mentioned single blow action, I illustrate a short crushing zone, which is substantially shorter than that of a conventional gyratory crusher. The upper and lower crushing elements are restricted in radial extent to provide a crushing zone which is so short that the majority at least of the particles of material passing through the zone are struck a single blow before they are discharged from the zione.

A further feature of the invention is the provision of a lower crushing element which includes an annular trough, the radial outer wall of which constitutes a weir preceding and leading to the crushing zone. This construction may be advantageous when the material is to be treated in a wet and uent state.

An embodiment of the invention is illustrated in the accompanying drawings in which Figure l is a vertical section of the relevant portions of the crusher;

Figures 2 and 3 are plan views of the ring that provides the upper crushing element and show alternative ways of securing it to the supporting member;

Figure 4 is a section on the line 4 4 of Figure 3; and

Figure 5 is a partial radial section through a variant form.

To a large extent, the crusher is conventionally built. It includes a head 2 which is mounted for gyratory movement on a main shaft 3 and which provides a mantle 4. The mantle is held fast by a nut 5 which screws on to the screw-threaded end of the main shaft 3 and which provides a platform 6 for a feed plate 7.

The crusher includes also an adjustment ring 8 of orthodox pattern.

Thenceforward, however, the crusher deviates from the nor-rn, since the conventional bowl structure is omitted. ln its place there is a ring 9 which is of L- section, the edge l0 of the limb 9a constituting the upper crushing element. The limb 9b overlaps a radially inward flange 11 provided on the inner wall 12 of a hollow cylindrical member 13 that supports the ring 9. The member is engaged by screw-threading 14 with the screwthreading 15 of the adjustment ring 8.

The lower crushing element is provided by the upper edge 16a of a second ring 16 which rests on the conical face 17 of the head 2. The mantle 4 bears against the radially inner edge 16b of a ange 16e` to locate the latter and the main body portion or ring 16, from the lower inner edge of which the ange 16e extends upwardly and inwardly to lie along the crusher head 2.

The crushing faces 10, 16a are conic and are substantially parallel with one another as shown in Figure l.

The ring 16 deiines an annular trough 18, the radially outer wall 19 of which constitutes a Weir which leads t0 the crushing zone 20. This construction is advantageous when the crusher is handling material in a wet and tluent state.

The ring 9 is fastened to the supporting member 13 by means which are accessible from above. Such means may be a series of U-bolts 21 and nuts 21a which clamp the limb 9b to the flange 11, as shown in Figure l. Alternatively, as Figure 3 shows, the ring 9 and member 13 may respectively provide a series of lugs 22 and a series of corresponding sockets 23, which collectively constitute a bayonet catch device. The ring is thus engaged with the member by rotational movement of the ring through a few degrees of arc to bring the lugs 22 into the sockets 23; the parts may then be locked together by a series of wedges 24.

The inner diameter of the ring 9 is preferably greater than the outer diameter of the feed plate 7. Thus if the crushing faces 10 and 16a are to be inspected, the nuts 21a are removed (or the bayonet connection broken) and the ring is removed by lifting it through the cavity of the member 13. This operation may be facilitated by providing several hooks 25 on the upper surface of the ring 9. As there is no need to dismantle any of the Crusher structure (save possibly the feed chute) the removal of the ring is easily and quickly done.

Removal of the ring 16 for replacement is almost equally easily effected since it is necessary only to unscrew the main shaft nut 5 and the mantle 4 and the ring can then be lifted out of the Crusher.

It will be seen that the crushing zone 20 between the crushing faces 10, 16a is considerably shorter than is the case in known crushers of the gyratory type. The zone is so dirnensioned that particles passing into the zone are struck only a single blow before they escape. lt may happen, however, that a proportion of the particles manage to slip through the zone unstruck. To minimize complete evasion, there may be several crushing zones through which the particles pass in turn. In Figure 5 the rings 9 and 16 are shaped to provide two sets 9x, 16x and 9)', 16y of crushing faces, spaced apart to define between them an annular trough 18 which receives particles emerging from the crushing zone 20x, where they form a mass which, supplemented by the inflow from the zone 20x, overows the Weir formed by the wall 19 and passes through the crushing zone 20y, to discharge. The possibility of particles passing through the Crusher uncrushed is thus greatly decreased.

Applicant has found that a Crusher of the type described is capable of a duty superior to the conventional crusher of equivalent size in respect of ne crushing, while the disadvantage of packing in the lower zone is eliminated by the quick discharge of the crushed material; with the added advantage of lower cost-due to the shorter liners-and easier maintenance.

It will be realized that whereas I have described and shown practical and operative forms of my invention, nevertheless many changes may be made in size, shape, number and disposition of parts without departing from the spirit of my invention. I therefore wish my description and drawings to be taken as in a broad sense illustrative or diagrammatic, rather than as limiting me to my specific disclosure herein.

The use and operation of my invention are as follows:

I illustrate herein opposed crushing members which have a number of advantages. In the first place, by merely removing or releasing the bolts 21, or their equivalent, the ring 9. which constitutes the upper crushing member, can readily be removed upwardly from the Crusher without dismantling the crusher. Preferably the inner aperture of the ring 9 is of sufcient diameter to permit the ring to be upwardly withdrawn without removing the plate 7. However, when both crushing members are to be removed, the plates 7 will have to be removed in any event to permit the upward withdrawal of the inner or lower ring 16.

The above-mentioned wear taking parts are admirably adapted to what I iind to be a substantial improvement in crushing practice, namely the crushing of particles by a single nip between opposed crushing surfaces which are substantially shorter than the crushing surfaces of conventionally designed gyratory Crushers. The two rings, or the upper and lower crushing members, are so designed as to deiine together a wall, the lower half of which constitutes a substantial dam or weir over which particles escape only to the crushing cavity proper. While a single pair of opposed rings may be adequate, I have illustrated in Figure 5 multiple opposed crushing rings,

I claim:

l, In a gyratory crusher, a head and means for gyrating it, and a bowl structure surrounding the head,

lll

said bowl structure including a hollow member open from above, an upper crushing ring removably mounted in said hollow member and an opposed lower crushing ring removably mounted on said head, the rings together defining with the head an annular trough, the radial outer surface of which is broken by a crushing gap between the two members at a point substantially intermediate the top and bottom of said trough.

2. The structure of claim l, characterized in that the upper and lower crushing rings are provided with a plurality of radially spaced opposed crushing surfaces said crushing surfaces being spaced equal distances above said head, and deiining between each pair of opposed crushing surfaces, in cooperation with said head, an annular trough.

3. A gyratory crusher, including a head and means for gyrating it, and a bowl surrounding said head, said head having an upwardly open trough located to receive particles fed from above, said trough being bounded by a weir over which particles may pass to a crushing zone between head and bowl said weir extending substantially vertically upward from said head for a distance substantially equal to the length of said crushing zone.

4. A gyratory crusher, including a head and means for gyrating it, and a bowl surrounding said head, an upper crushing ring mounted on said bowl for axial removal therethrough, a lower crushing ring mounted on said head for axial removal through said bowl, the innermost inside diameter of said bowl above said crushing zone exceeding in magnitude the outside diameter of said upper and lower crushing rings, said rings bounding a feed receiving cavity having a generally cylindrical substantially vertical inner wall broken intermediate its upper and lower edges by a crushing zone formed by the opposed crushing surfaces of the two rings.

5. As a new article of manufacture, a lower crushing ring for gyratory Crushers and the like, said ring including a circumferential main body portion terminating at its upper edge in a downwardly and outwardly conic top crushing surface, said body portion having substantially vertical inner and outer walls, said body portion having extending upwardly and inwardly from the lower edge of said inner vertical wall a flange adapted to seat upon the generally conic head of a gyratory crusher.

6. The structure of claim 5, characterized in that the lower surface of the flange and the adjacent lower surface of the body portion together constitute an upwardly and inwardly conic continuous surface adapted to conform to a generally conic supporting surface of the head of the gyratory crusher.

7. In a gyratory crusher, a hollow member and means for supporting it at least partly above the crushing zone, a ring adapted to form the upper crushing element of the crusher, detachably secured to and surrounded by the hollow member, the innermost inside diameter of the hollow member above the crushing zone exceeding in magnitude the outside diameter of the crushing face of said ring whereby the ring may be inserted and removed through the hollow member, the hollow member being open from above, an opposed lower crushing element, and a crushing head on which it is supported, and means for gyrating the crushing head, the Lipper crushing element including a radially projecting flange and the hollow member including an inward projection having an inside diameter exceeding in magnitude the outside diameter of the crushing zone, and means accessible from above through the top of the hollow member for securing said flange to said projection, said securing means being constituted by a bayonet catch device actuable by rotational movement of the ring.

8. In a gyratory crusher, a ring-like upper crushing element, a hollow support for said crushing element, means for supporting said hollow support at least partly above the crushing zone, said upper crushing element being detachably secured to and surrounded by said support, the innermost inside diameter of said support above the crushing zone exceeding in magnitude the outside diameter of said crushing element whereby the ring may be inserted and removed through the support, the support being open from above, an opposed lower crushing element and a crushing head on which it is supported and means for gyrating the crushing head, said upper crushing element including a radially projecting flange adjacent its upper outer edge, said support including an inward projection having an inside diameter exceeding in magnitude the outside diameter of said crushing element below said ange, and means accessible from above through the top of said support for securing said flange to an upper surface of said projection.

9. In a gyratory crusher, a ring-like upper crushing element, a hollow support for said crushing element, means for supporting said hollow support at least partly above the crushing zone, said upper crushing element being detachably secured to and surrounded by said support, the innermost inside diameter of said support above the crushing zone exceeding in magnitude the outside diameter of said crushing element whereby the ring may be inserted and removed through the support, the support being open from above, an opposed lower crushing element and a crushing head on which it is supported and means for gyrating the crushing head, said upper crushing element including a radially projecting flange adjacent its upper outer edge, said support including an inward projection having an inside diameter exceeding in magnitude the outside diameter of said crushing element below said ilange, and means accessible from above through the top of said support for securing said ange to an upper surface of said projection, said opposed lower crushing element having an outside diameter less than the inside diameter of said inward projection whereby said opposed lower crushing element may be inserted and removed through the support.

10. As a new article of manufacture, an upper crushing ring for gyratory Crushers and the like, said ring including a substantially cylindrical rnain body portion having locking members outwardly projecting therefrom adjacent the upper, outer edge of said main body portion, said main body portion having an upwardly and inwardly conic lower surface constituting the entire crushing surface of said crushing ring, the substantially cylindrical inner and outer walls of said main body portion rising upwardly, respectively, from the inner and outer edges of said crushing surface.

References Cited in the file of this patent UNITED STATES PATENTS 431,069 Lowry July 1, 1890 1,953,472 Fahrenwald Apr. 3, 1934 2,148,682 Campbell Feb. 28, 1939 2,438,049 Gruender Mar. 16, 1948 2,468,342 Munro Apr. 26, 1949 2,509,920 Gruender May 30, 1950 2,579,238 Lippmann Dec. 18, 1951 FOREIGN PATENTS 555,353 Germany July 22, 1932 656,857 Germany Feb. 17, 1938 

